Cerebral vasodilators and cerebral excitometabolic agents are being employed as therapeutical agents for the treatment of diseases such as dementia and amnesia. These agents are effective for the treatment of diseases such as dementia caused by cerebrovascular disorders. However, these agents do not show a sufficient therapeutic effect for the treatment of dementia-type diseases due to causes other than cerebrovascular disorders.
With respect to the present invention, 2-pyrrolidone-5-carboxylic acid compounds of pertinent interest have been published in the technical literature. For example, Chemical Abstracts, Vol. 85, No. 19, 142978d (1976) discloses the compounds represented by the general formula: ##STR4## where m is an integer with a value of 1-4. These compounds exhibit a mild antibacterial effect, and are useful as cosmetics such as deodorants and skin conditioners. There is no disclosure in the literature that these compounds have potential application as therapeutical agents for the treatment of mental disorders such as dementia and amnesia.
Chemical Abstracts, Vol. 100, No. 5, 34562h (1984), discloses the compound represented by the formula: ##STR5## which is useful as an intermediate for the production of antihypertensive agents. There is no disclosure in the publication of any biological activities exhibited by the compound.
Chemical Abstracts, Vol. 80, 82678r (1974), discloses the compound represented by the formula: ##STR6## which is illustrated as one of 3-pyridine methanol derivatives having vasodilating activities, and having utility as vasodilators and psychotropic agents. There is no disclosure or suggestion in the publication that the compound might be useful as a therapeutical agent for the treatment of dementia and amnesia.